Telescreens are devices that operate as televisions, security cameras, and microphones. They are featured in George Orwell's dystopian 1949 novelNineteen Eighty-Four as well as all film adaptations of the novel. In the novel and its adaptations, telescreens are used by the ruling Party in the totalitarianfictional State of Oceania to keep its subjects under constant surveillance, thus eliminating the chance of secret conspiracies against Oceania. All members of the Inner Party and Outer Party have telescreens in their homes, but the proles are not typically monitored as they are unimportant to the Party. As later explained in Emmanuel Goldstein's book of which Smith reads some excerpts, the Party does not feel threatened by the Proles, assuming that they would never rebel on their own, and therefore does not find a need to monitor their daily lives. The character O'Brien claims that he, as a member of the Inner Party, can turn off his telescreen. While the programmes could no longer be seen or heard, the screen still functioned as a surveillance device, as after Winston is taken into the Ministry of Love, the audio of his meeting with O'Brien with the telescreen "off" is played back to Winston. Winston, a member of the Outer Party, can only turn the volume on his telescreen down. The screens are monitored by the Thought Police. However, it is not clear how many screens are monitored at once, or what the precise criteria for monitoring a given screen are. Telescreen cameras do not have night vision technology, thus, they cannot monitor in the dark. This is compensated by the fact that their microphones are extremely sensitive, and they are said to pick up a heartbeat. As Winston describes, "... even a back can be revealing..." In addition to being surveillance devices, telescreens are also televisions. They broadcast propaganda about Oceania's military victories, economic production figures, spirited renditions of the national anthem to heighten patriotism, and Two Minutes Hate, which is a two-minute film of Emmanuel Goldstein's wishes for freedom of speech and press, which the citizens have been trained to disagree with through doublethink. Many of the telescreen programmes are transmitted in Newspeak.